INTEGRATION of FUNDAMENTALS in the LAST YEAR of the UNDERGRADUATE CHEMICAL ENGINEERING COURSE* BARNETT I?. DODGE Yale University, New Haven, Connecticut
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T IS my intention in this paper to outline very briefly a general philosophy of the undergraduate course in chemical engineering which has been slowly evolving as a result of about fifteen years of
* Contribution to the Symposium on Chemical Engineering Education, conducted by the Division of Chemical Education at the ninety-fourth meeting of the A. C. S., Rochester, N. Y., September7.1937.
teaching experience and to show how the main points of this philosophy may be put into practice with particular reference to the curriculum of the senior year. There is nothing radically new about my concept, but it seems to me that i t does lead to a combination of comes in the last year which is quite differentfrom that in the engineering I shaU avoid the issue as to the most desirable length
of time for an undergraduate course. What I propose can undoubtedly be done more satisfactorily in five years than four years. I am not even sure that it is possible to do it in four years, but I shall confine my specific proposals to the last year and i t is immaterial to the argument whether i t be the fourth or fifth year. I shall limit my discussion to technical courses. This does not mean that cultural or humanistic studies are to be omitted from the curriculum. I firmly believe that there shodd be a continuous thread of cultural development throughout the undergraduate course, but that is another story which is beyond the scope of the present discussion. Briefly stated, my thesis is that the first three (or four) years of the course should be devoted to learning the fundamental facts and principles of certain basic sciences, without much regard to their application to actual engineering situations and the last year should be of a wholly different character in that the emphasis shifts entirely from primarily storing knowledge to applying the accumulated knowledge to solve problems of the type that one is likely to meet in the practice of engineering. This is scarcely a novel idea, but if it is followed to a logical conclusion, it seems to me that it ought to lead to a greater differentiation between the senior year and the preceding years than that which prevails at the present time in the average engineering course. Before attempting to translate my ideas into the concrete form of courses and a curriculum i t may be well to review some of the most important general objectives of an engineering course. These are fairly obvious truisms, but I find it highly desirable to review them frequently so that they are constantly available as guides to direct one's thinking about curricula. I t is commonly said that we should endeavor to train men to become engineers after they graduate. This is a very simple but highly important concept. To me it means the elimination from the curriculum of all specialized courses that deal wholly with the details of a particular industry or of any narrow field. We should avoid all pleas to give this or that special course because the graduate ought to know something about the subject when he gets out into industry. It is impossible to build a curriculum on such a basis. We must select for the three (or four) years of essentially pre-engineering training about which I have spoken, only those subjects which have broad application to all of chemical industry and to confine ourselves to facts and principles of fundamental significance. Side excursions into the details of some special field are only justified as a means of illustrating some principle which is applicable in other fields as well. Three years is all too short a time in which to make even a good beginning toward the real understanding of fundamentals, and, if we divert some of this time to other uses, it is clear that we must sacrifice something that is of peater importance to our stated objective.
It is also generally agreed that we are trying to train men who can do constructive thinking rather than be routine technicians. The latter can perform very satisfactorily under situations which duplicate or are similar to those for which they have received specific training, but they fail when confronted with new situations that call for initiative and originality. A certain number of such men are highly useful in industry, but the universities should a t least strive to develop men of a higher type-men who can analyze a new situation in terms of fundamental principles and then formulate a plan for action. There has been much argument both pro and con on the subject of teaching students to think for themselves. I have no panacea to offer. I merely suggest that we devise the cumculum so that those men who have latent powers in this direction can find an opportunity to develop them by active exercise. There is too great a tendency to stifle any urge of this character by imposing such a requirement of things to be learned that there is no time for anything else. Obviously, in order to exercise the thinking power, one must have something to think about. Many facts must be stored in the mind ready for instant marshalling. Many technics of a routine nature must also be acquired. In other words, the developing engineer must be equipped with many tools before he can expect to even make a start on the attack of engineering problems. But let us try to select a minimum number of the most important facts and principles to be learned and then allow some time in the curriculum for the student to acquire practice in their application under conditions that call for as much mental effort as possible on his part. I t is well recognized that the problems which the young engineer is likely to meet in industry will seldom be just like any of those solved in the textbooks or handbooks. Furthermore, the field of chemical engineering is all the time becoming broader and more complex, and the natural tendency of those in industry is to expect the young graduate to know more and more things. The teacher, too, feels that he must cover so much ground in order to give the young engineer an adequate preparation to meet future problems, and consequently he tends to add more and more material to the curriculum. It is plainly futile to attempt to meet the situation in this way. What we really need is less emphasis on subject matter and more emphasis on showing the student how to generalize from a minimum of facts and how to utilize material which he can refer to when occasion demands. Summarizing briefly, the two main objectives of the undergraduate chemical engineering course are: (1) To equip the student with a selected number of facts, principles and technics from the basic sciences so that he has a kit of tools with which to start to go to work on engineering problems. (2) To give him practice in marshaling his knowledge and bringing hitherto unrelated parts of i t to a common focus for the solution of engineering problems. It is
this bringing together of facts and principles from a variety of fields to aid in the solution of a comprehensive problem that is the process of "integration" to which I referred in the title of this paper. I imagine that most teachers of chemical engineering would not disagree with me to any great extent on the general objectives which I have outlined. There is, however, considerable disagreement on how these objectives are to be realized. A certain amount of disagreement is natural and desirable. I should not wish to see all chemical engineering curricula cast from the same mold. I do believe, however, that many curricula in operation a t the present time are in serious need of revision to bring them in line with these objectives.
acquaintance with the scientific fundamentals will already have been secured from the course in physical chemistry. Some may quarrel with my inclusion of elements of electrical engineering and unit operations of chemical engineering in the engineering sciences. They are, of course, applied sciences based on the more fundamental sciences, but I regard an elementary knowledge of these two subjects as essential tools that the student needs before he can begin to attack any comprehensive problem in chemical engineering without too much lost motion. On this basis I include them among the subjects to be covered before the final year. This is particularly true of the unit operationsthose fundamental operations of heat transfer, fluid flow, distillatiori, filtration, and the like which underlie the whole of GENERAL OUTLINE OW PROPOSED CURRICULUM chemical industry and which are now firmly established To carry out the foregoing objectives I propose to as the backbone of modern chemical engineering have three (or, if necessary, four) years devoted to the courses. acquisition of the fundamentals of the basic sciences, Before coming to the work of the senior year there is followed by a final year which is given over entirely to one point which I should like to mention about which the solution of comprehensive problems of an engineer- there has been considerable argument. It is my belief ing character. The basic disciplines in which i t is that all the courses in basic science should be definitely desirable that some familiarity with the fundamentals considered as preparatory to the later engineering be acquired might be classified as follows: courses and the subject matter chosen with this end (1) Basic sciences: The three fundamental sciences in view. This means that in mathematics, physics, of chemistry, physics, and mathematics. physical chemistry, and so forth, emphasis should be (2) Social sciences: Elements of economics and placed on those facts and principles which can be disome applied economics. rectly utilized in the work of succeeding courses, and (3) Engineering sciences: Engineering drawing, me- material of purely theoretical interest should be chanics, materials of construction, thermodynamics, omitted. This strictly practical point of view seems to elements of electrical engineering, and unit operations me to be entirely in line with the general concept of the of chemical engineering. curriculum already presented. Furthermore the enIn chemistry I would have only the basic courses in gineering student is very impatient with those things the four well-recognized divisions, namely, general and which appear to him to have no practical value. It is inorganic, analytical, physical and organic. Note that important to maintain his interest by concentrating I would omit all such courses as industrial chemistry, on those parts of a given subject which can be applied chemistry of fuels, water analysis, electrochemistry, and to illustrate the application continually by suitable and many others which now occur in some chemical problems. engineering curricula. I do this on the ground that It is d i c u l t to realize this type of course in practice these courses are largely descriptive and informational as it means close coiiperation between the engineering in character, and the time can be utilized to better ad- and science departments and frequently necessitates vantage on more fundamental things. special courses for the chemical engineers. There would be the usual basic course in physics. The senior year of the proposed course is to be quite Mathematics should be carried through differential different from the preceding one. In the first three and integral calculus with an introduction to elementary (or four) the emphasis was on individual subjects. The differential equations. elements of each subject had to be learned without I confess that I am not clear in my own mind how far particular reference to their interrelationships or theit to go in the social sciences. I think most would agree significance to any specific engineering problem. The that there should be a course in general economic disorganized individual threads must somehow be intheory. I believe that i t would be desirable to follow tegrated, or woven into some kind of a unified and this with a course in what, for want of a better name, I ordered pattern. I believe that the best way to do have called applied economics. It would deal with this is to shift the emphasis entirely from individual such things as labor problems and other human rela- subjects and center all the work of the senior year tions in industry, with elements of cost accounting, around a small number of comprehensive problems or problems of buying and marketing, tariffs, patents, and projects,, selected as far as possible to represent real related questions. engineering situations like those encountered in pracI have included thermodynamics among the engineer- tice and to involve as many of the fundamentals preing sciences because I believe that it should be taught viously studied as is feasible. to engineers from an engineering point of view. An I would have no lecture courses, or formal laboratory
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c6mses' or any.l:+eeific':'&&ignments in textbooks. There would b e cl& meetings for purposes of discussion. The students would consult many books, not because certain passages were assigned to be learned, but : o n ,their own initiative 'because they needed soine information for the solution of a problem. Stlbject matter is decidedly secondary. There must be no attempt to cover ground as this will defeat the whole purpose of the scheme. THE COMPREHENSIVE PROBLEM
I shall digress f o r a moment to explain in a more concrete way what I mean by a comprehensive problem. The usual problem given in a specific course such as pEysical chemistry or unit operations is one of very limited scope and with the conditions all well defined bfr the instructor. In fact, he strives hard to define and qualify the problem so carefully that a minimum of questions will be raised in the student's mind. This is, of course, quite the opposite of any real engineering problem which is poorly defined a t the start and immediately raises a host of questions. This type of problem, which I will call the simple problem in contrast to the comprehensive one, can generally be readily solved by formulas given in the textbook or by data obtained from a handbook. Most of the thinking has already been done by the instructor, and it is probable that he is the one who gains the most from it, rather than the students. However, this type of problem is useful, and, I believe, essential to the process of learning the fundamentals of a particular subject. We should recognize that the solution is little more than a routine procedure once the principles expounded in the text are read and understood. The comprehensive problem has a simple and welldefined objective. On the other hand, the trail leading to the objective is not only very ill-defined but there are apt to be a large number to choose from, most of which lead to dead ends, necessitating frequent retracing of steps to make a fresh start. In other words, i t cannot be solved simply by reference to formulas or handbooks. It is broad enough so that it must be attacked from various angles and with a variety of tools. I t must be analyzed to reduce it to a number of simple problems. This process will give plenty of opportunity for the student to exercise judgment and ingenuity and to bring together data and principles from hitherto unrelated fields. Comprehensive problems should be real (as distinct from artificial) problems of a practical character, and this presupposes that the engineering teacher has sufficient contact with industry so that he can devise such problems. This is another story beyond the scope of the present paper. Let me illustrate the comprehensive problem by a concrete example. Assume that a plant is using a certain solvent which is simply evaporated into an airstream and lost. It is desired to determine the feasibility of recovering the solvent in a, form available for re-use. This is a statement of arompr6hensive problem
in a very general form. The ultimate objective is simple and clear, but the means to reach the objective are very obscure. There is no formula that one can find anywhere which will furnish an answer to the problem. Such a problem will completely baffle any student who is used to having his thinking all done for him and his problems all analyzed and dished up in such finished form that all he has to do is to turn a crank and grind out a result. Obviously, this is a very broad problem, and we must narrow it so that a student may reach some conclusion in a limited amount of time. The first problem assigned might be to decide on the general outline of the process that is to be tentatively selected for further study. This will involve a consideration of the fundamentals underlying the condensation of vapor in a mixture of vapor and non-condensable gas to a liquid. Several general methods such as refrigeration, compression and cooling, absorption in a liquid absorbent, or adsorption on a solid adsorbent might be used. A decision in favor of one of them must be made and supported by facts. The details cannot be entered into here, but i t should be evident that the solution will involve the bringing to a focus of knowledge from several Merent fields and is far from a routine matter. In the course of his analysis of the comprehensive problem the student will set for himself many simple problems of the type he has learned to do in specific courses. The difference, and it is a very important one, is that now he sets up the problem himself. Consequently, it means much more to him than if the instructor had done it. For example, in the course of weighing the advantages and disadvantages of the various processes for solvent recovery, he will set himself the problem of calculating the power requirement to recover a gallon of solvent by the compression process, assuming various specific conditions. This is information that he must have in order to arrive a t an intelligent decision. The final solution of the problem will be a report setting forth the various possibilities and then a recommendation of one of them accompanied by all the supporting arguments. Having chosen the process in general outline, another comprehensive problem would be to choose the detailed conditions of operation-pressures, temperatures, concentration, rates of flow, and so forth. This will involve many simple problems in physical chemistry and in the unit operations of chemical engineering. The final problem will be a matter of economic balance to arrive a t an estimate of the cost of recovery, which is the ultimate objective. This is necessarily a very sketchy outline but, I hope, sufficient to convey a general idea of the type of problem I have in mind. CURRICULUM OF THE SENIOR YEAR
As a specific proposal, it is suggested that there be not more than four technical courses in the year, each centering around a different type of comprehensive problem or project. I will outline these briefly as follows.
(1) A Calculation Course Based a the Economic Balance Type of Comprehmsiere Problem, an Example of Which Has Been &a,-There would be no laboratory work in this course and the two or three class meetings a week would be informal and devoted to the discussion of the many questions that arise as the work on the problem proceeds. From four to eight problems would suffice for the year, and they should be selected to involve as many of the subjects studied in the preparatory years as possible. It is also well to start with relatively simple problems because problems of this type will be a new experience for the students, and there will be a great deal of floundering until they have acquired a little confidence. Problems like the annual contest problem for the Student Chapters of the American Institute of Chemical Engineers are well suited to the needs of this course. (2) Plant or Equipment Design Project.-The problems of this course will be solved mainly on the drawing board. At least the final result will appear in this form, though much of the time will be devoted to searching for data and making calculations. The problems may be individual, or the whole class may work on the same problem. Both systems are used, but I prefer the latter. The use of individual problems places too heavy a burden on the instructor. Two or three problems are all one can hope to undertake and they can often be advantageously correlated with problems used in Course 1. After the flow sheet and general operating conditions for some process have been arrived a t by the work of Course 1, the problem can then be carried further under this second course. It may involve either the selection and arrangement in the plant of standard equipment, or it may take the form of the detailed design of some piece of special equipment. (3) A Laboratory Project.-This is simply a comprehensive problem, but one for which some of the necessary data are lacking, and the objective of the project is to supply these data. For example, in the case of the solvent recovery problem already used as an illustration of problems under Course 1, i t may be that the calculation of the size of a heat exchanger or of an absorption tower is hampered by lack of data on rate coefficients or data on pressure drop due to flow or on vapor pressure of the solution of the vapor in the absorbent and the object of the project is to secure the data by experiment. The project does not need to be of a research character like the ones just outlined but may involve a test on some equipment. The nature of the problem is not important, as long as the student himself has to plan the method of attack to reach the objective, and as long as it involves some application of fundamentals previously learned. Frequently, the original statement of the problem is quite broad and indefinite and the student, in consultation with the instructor, must narrow it and make i t more specific. This, in itself, is excellent experience. The laboratory project also gives useful experience in
searching literature, formulating a plan of attack, designing and operating equipment, and interpretation of experimental results. ,Throughout the whole course of the work, the reliance on fundamentals is stressed and driven home on every suitable occasion. Our laboratory project course runs for eight hours a week throughout the year. The students have individual problems, and each is assigned to a project advisor. There are no regular class meetings and no regular meetings between the student and advisor, but i t is the responsibility of the latter to keep in close touch with the student's work, to help him when he comes to an impasse, to see that he has the facilities he needs, and to keep him steered in the right direction. (4) Reports.-Much has been written and said on the subject of the inability of the average engineering graduate to write clear, concise, readable reports. The only way to help this situation is to give the student practice in writing under guidance and criticism. Courses in English may help a little but they do not get to the root of the matter. From my own experience in teaching students to write reports, it is clear to me that the major difficulty is not with the grammar or the sentence construction but simply lack of ability to organize their material. This can be learned only by experience. In order to write a good report, one has to have something from his own experience to write about-something that is vivid and alive for him. I find that the laboratory project "fills the bill" very well. In my own case, I require four reports during the year on the project. The first one is due a few weeks after the students have started their work and is a short one giving a statement of the problem, its relation to a broader problem, and an outline of the proposed method of attack. It is surprising how difficult i t can be to write a paper which is apparently so simple to organize. These reports are criticized severely and must often be re-written. After about three months of work on the project, a progress report is due and everything done in this period has to be digested, organized, and presented in good form. This is also severely criticized and gone over individually with the student. A second progress report about the middle of the second term summarizes the first one and then presents the subsequent progress. A final, bound report is due a t the end of the year, and this must be a complete report on the whole problem. One or two oral reports are also desirable to give the students some experience in this form of expression. Here again the laboratory project furnishes the subject matter. The program for undergraduate instruction in chemical engineering which I have outlined is somewhat idealistic in that i t has not yet been wholly worked out in practice. It indicates the direction in which we are working to shape the course given a t Yale. There are many practical difficulties in the way, but we have
made distinct progress. What I have in mind may, graduates do not return for advanced work, I believe it perhaps, he comparable to the four-year course followed is better to incorporate these ideas in the undergraduate by a fifth year of graduate work as now practiced at course and devote the graduate years primarily to some schools; but since about eighty per cent. of our training in research.
